Throttle control device



May 9, 1939. M. MERRIMAN THROTTLE CONTROL DEVICE Filed July 13, 1938 2 Sheets-Sheet l INVENTOR. BY fimrq /7 Nff/fT/Ufl A ORNEYB' y 1939- H. M. MERRIMAN 2,157,652

THROTTLE CONTROL DEVI CE Filed July 13, 1938 2 Sheets-Sheet 2 460 P 6q/ .4 .Z J5

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INVENT OR.

* emmgz AT ORNEY5 Patented May 9, 1939 UNITED STATES PATENT OFFICE 17 Claims.

This invention relates to improvements in throttle control devices.

The main objects of my invention are:

First, to provide a throttle control device for automotive engines to retard the rate of opening of the throttle during acceleration in accordance with the ability of the engine to utilize fuel vapor while picking up speed.

Second, toprovide a device of the type described including a novel brake mechanism to retard opening of the throttle of an internal combustion engine and under the control of the vacuum existing in the intake manifold thereof.

Third, to provide vacuum controlled brake means for governing acceleration of an internal combustion engine.

Further objects relating to details and economies of my invention will definitely appear from the description to follow. The invention is defined in the claims.

A structure embodying the features of my invention is illustrated in the accompanying drawings, wherein:

ig. 1 is a fragmentary view partially in section illustrating an internal combustion engine of well-known type with the control device of my invention operatively mounted thereon.

Fig. 2 is a fragmentary view partially in vertical transverse section illustrating details of construction of the brake unit of the device.

Fig. 3 is a fragmentary View mainly in section on line 3-3 of Fig. 2 further illustrating details of the device.

Fig. 4 is a fragmentary View mainly in vertical section of a modified form or embodiment of my invention.

Fig. 5 is a fragmentary view partially broken away and in section on line 55 of Fig. 6, illustrating a still further modified embodiment of my invention.

Fig. 6 is a fragmentary view in section on line 65 of Fig. 5, further illustrating details of the last named embodiment.

The present invention relates to a device for retarding the opening of the throttle valve of an internal combustion engine whereby the throttle will not be opened out of proportion to the ability of the engine to consume fuel vapor admitted thereto. The tendency of many drivers to depress the accelerator pedal fully for the purpose of accelerating quickly results in gasoline or other fuel passing into the motor in a liquid form, which liquid fuel is wasted so far as conversion into power is concerned and only serves to dilute the oil in the crankcase and to wash the lubricant from cylinder and piston walls, thereby greatly increasing wear. I overcome this condition by the provision of a brake connected with the accelerator mechanism to retard the manual opening of the carburetor control valve when the vacuum in the intake manifold is below a predetermined strength. When a higher degree of vacuum exists in the intake manifold, the brake is off, by reason of the provision of vacuum responsive means connected with the intake manifold for releasing the brake, but when the vacuum drops below a predetermined value the brake again becomes effective and the carburetor can be opened further only against the brake until the engine revolutions increase to a point at which the fuel vapor passing through the carburetor is entirely consumed.

Referring to the drawings, the reference numeral l in general indicates an internal combustion engine having a carburetor 2 provided with a throttle valve shown by dotted lines. The valve operating arm is designated by the reference numeral 3. The throttle valve controls the passage of fuel vapor from carburetor 2 to an intake manifold 4 in the usual manner. The arm is manipulated by the operator through a rod 5 and the lever 15 pivoted on the floor board of a vehicle 7 powered by the engine. This may be a truck, bus, tractor, pleasure vehicle, or the like. The usual foot pedal 8 is provided to actuate the throttle.

The control device of the embodiment of my invention illustrated in Figs. 1, 2 and 3 consists of a circular casing or housing 9 having a fixed central spindle in extending between the side walls il thereof. This spindle serves as an anchor for one end of a spiral spring l2, the other end of which is attached to a brake drum [3 having a pulley or sheave l4 formed as a part thereof and rotatable in the spindle, see Fig. 3. This pulley has attached thereto at [5 a pull cord or cable I6 which passes outwardly through an opening Ii in casing 9 and is attached to rod or link 5 by means of a suitable clamp IS. The housing 9 is mounted on the engine block in any suitable manner as, for example, by means of a bracket I9 suitably held on the spindle ID.

The spiral spring l2 normally urges cable 16 in a direction to close the throttle valve and thus serves as a return spring when the accelerator pedal 8 is released.

Within the housing 9 I provide a centrally apertured bracket 29 having a pair of angled upwardly extending guide members 2| which terminate in opposed parallel guide fingers 22. The bracket 29 is screwed to the housing in a locating depression 23 at the bottom thereof, with the aperture in the casing alined with a central aperture in the depression. The guide fingers 22 are slidably engaged by a segmental brake shoe 24 provided with a suitable lining 25 of friction material, and it will be appreciated that when the brake shoe is urged against the drum [3, angular movement of the latter is retarded or stopped.

The reference numeral 26 indicates a two-piece housing or casing between the parts of which a flexible diaphragm 2'l is clamped. The casing is secured to the housing 8 in any suitable manner as, for example, by spot welding, and it has a central aperture in line with the apertures in the bracket 29 and housing 9 to form a communicating opening 21! between the interiors of the housing 9 and the casing 26. One side of the diaphragm is provided with an upstanding threaded thrust element 28 on which is adjustably secured a round head nut 29 in thrust engagement with the rear of brake shoe 24. The other side of the diaphragm is engaged by a coil compression.

spring 30 which is received in hollow sleeve or coupling 3i connected to the diaphragm housing and which abuts a suitable fixed supporting rest or shoulder (not shown) within the coupling, whereby to continually urge thrust member 28 upwardly as viewed in Fig. 3 to engage brake shoe 24 with drum l3. The hollow coupling 3i is in communication with intake manifold 4 through a suitable conduit 32.

From the foregoing description it will be apparent that the friction between the brake shoe and drum is sufficient to retard rapid actuation of arm 3 of the throttle valve, although the throttle valve will be opened a certain amount to permit vapor to pass to the engine, thereby increasing the speed of rotation of the same. This increase in speed results in a greater vacuum in the intake manifold, with the result that the vacuum acting below the diaphragm 31, as viewed in Fig. 3; causes the latter to move downwardly and decrease the thrust pressure on brake shoe 24. This decreases the friction generated between the brake elements and allows cable [6 to be pulled to the right as viewed in Figs. 1 and 2, or reduces the resistance to the actuation of the accelerator pedal to complete the opening of the throttle valve. When the accelerator pedal 8 is released, spring l2 returns the throttle valve to proper position.

In Fig. 4 I illustrate a modified embodiment of my invention which is generally similar to that illustrated in detail in Figs. 2 and 3, save for the fact that a disk type of brake, similar to a multiple disk or Weston clutch, has been substituted for the segmental shoe and drum type. Sheave 33 has oppositely extending annular flanges 34, 35, tothe former of which one end of a spiral spring 38 is secured with its other end anchored onthe fixed spindle 31.

The other flange 35 has a plurality of axial keys or splines 38 slidably engaging the centrally apertured brake disks 39; The spindle 31 telescopes with a hollow boss 40 of a brake compressor member 4|. Boss 48 carries keys or splines 42 on which are slidably mounted the disks 43, alternating with the disks 39 axially of flange 35 and boss 48. Compressor member 4| is urged to the left as viewed in Fig. 4 by a thrust member 28 and adjustable nut 29 thereof which are similar to those illustrated in Figs. 2 and 3 and need not be again described in detail. It will be noted that in Fig. 4 the bracket 44 for securing the device to the engine block or head has been altered slightly in design and method of securement to the casing 9 and housing 26 without, however, altering the manner of operation of the other parts.

In Fig. I illustrate a further embodiment of m invention. This structure may be produced at slight cost. It consists of a cylindrical or tubular housing 45 having one end thereof closed by the plug-like member 46. This tubular housing is connected to a diaphragm housing 26 and to the bracket 41 by means of the strap 48 which surrounds the housing 45 and clamps it in position. This strap 48 has out-turned feet 49 secured to the bracket 4'! by means of screws as shown in Fig. 6. Within the housing is a fixed friction member 50 and in opposed relation thereto is a movable friction member 10. These friction elements 50 and in the embodiment illustrat'ed are of block-like form and are formed of wood. Their opposed faces are longitudinally grooved to provide a way 5| frictionally receiving the flattened bar-like brake element 52 which projects beyond the friction elements 50 and 10 at both ends. The inner end ll of the member 52 is of reduced width and provided with a thrust member 53 engaging a coiled spring 55. The other end of the coiled spring is seated against the thrust member 56 which is in turn supported by the friction element 50 secured in fixed position within the housing by the screws 51.

The friction or brake element 10 is capable of radial movement within the tube, this movement being controlled and effected by means of the thrust or coupling element 58 which connects the block to the diaphragm. The thrust member 28 being threaded, this connection is adjustable.

The element 58 has an ear-like extension 59 on its upper end carrying a transverse pin Bl] while the friction element 10 has a recess 6| therein receiving the ear. Slot-like notches 62 at either side of the recess 6| receive the pin'fifl. The diaphragm, diaphragm housing and spring arrangement are substantially that previously described.

In operation it will be seen that under a condition of low vacuum in the intake manifold the brake member ill will be under the thrust of the spring thus imparting a braking action to the bar 52 which is connected by the link 54 to the throttle. This retards the opening of the throttle valve but when the vacuum in the intake manifold increases this increase will be transmitted to the diaphragm in housing 26, thus drawing element 58 downwardly as shown in Figs. 5 and 6 and reducing or relieving the braking effect on the bar 52.

Structures embodying my invention have been used commercially with a very substantial saving in gasoline consumption, and this is particularly important on buses, trucks and the like which make frequent stops. The presence of the control device does not retard desirable acceleration 1" but serves as an effective warning to the operator, should he attempt to fully open the throttle in starting the vehicle. When that is done much unvaporized fuel is likely to be taken into the cylinders where it is not effectively consumed, and a substantial portion thereof is passed into the crank case and in passage Wipes or washes the lubricant from the cylinder and piston, resulting in increased wear. It is possible to fully open the throttle against the resistance of the brake should T occasion require but, owing to the resistance to the opening of the throttle, the operator soon becomes accustomed to its presence and operates the foot pedal as is contemplated to secure the highest efiiciency.

The results in the saving of fuel are repeated in a substantial measure in the saving of lubricant as where substantial amounts of fuel pass into the crankcaseit'is' necessary to replace the diluted lubricant more often; and this replacement of lubricant is an item of very substantial expense in the operation of buses and trucks.

I have illustrated and described my invention in embodiments which are very practical. I have not attempted to illustrate or describe other embodiments or adaptations as it is believed this disclosure will enable those skilled in the art to embody or adapt my improvements as may be desired.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. The combination with the throttle valve and intake manifold of an internal combustion engine and a manually operated throttle control member, of a housing having a fixed spindle therein, a brake drum rotatably mounted on said spindle, a pulley rotatable with said drum, a torsion spring connected at its ends to said spindle and brake drum, a tension member connected to said pulley to wind thereon and with said throttle control member for applying rotative movement to the drum in opposition to said torsion spring when the throttle valve is opened, a brake shoe operatively associated with said brake drum, a thrust member operatively associated with said brake shoe, a coiled spring acting on said thrust member to actuate said brake shoe, a diaphragm housing in communication with said intake manifold, and a diaphragm in said housing operatively connected with said thrust member whereby to retract the same under the influence of the vacuum in the manifold.

2. The combination with the throttle. intake manifold of an internal combustion engine, and a manually operated throttle control member, of a brake drum, a pulley rotatable with said drum, a spring acting to rotate said brake drum, a tension member connected to said pulley to wind thereon and with said throttle control member for applying rotative movement to the drum in opposition to said spring when the throttle valve is opened, a brake shoe operatively associated with said brake drum, a thrust member operatively associated with said brake shoe, a spring acting on said thrust member to actuate said brake shoe, adiaphragm housing in communication with said intake manifold, and a diaphragm in said housing operatively connected with said thrust member whereby to retract the same under the influence of the vacuum in the manifold.

3. The combination with the throttle valve and intake manifold of an internal combustion engine and a manually operated throttle control member, of a brake drum rotatably mounted on said spindle, a pulley rotatable with said drum, 2. spring acting to rotate said brake drum, a tension member connected to said pulley to wind thereon and with said throttle control member for applying rotative movement of the drum in opposition to said spring when the throttle valve is opened, a brake shoe operatively associated with said brake drum, a thrust member operatively associated with said brake shoe, a spring acting on said thrust member to actuate said brake shoe, and a vacuum actuated element operatively connected with said thrust member whereby to retract the same under the influence of the vacuum in the manifold.

4. The combination with the throttle valve and intake manifold of an internal combustion engine and manually operated throttle control means, of a brake operatively associated with said manually operated control means for retarding the actuation thereof comprising a brake drum, a spring acting to rotate said drum, a tension member connected to said brake drum and with said manually actuated throttle control means for applying rotative movement to the drum in opposition to said spring when the throttle valve is opened, a spring actuated brake shoe operatively associated with said brake drum, and a vacuum operated means operatively connected to the intake at the rear of said throttle and including a vacuum actuated element operatively connected to said brake shoe.

5. The combination with the throttle valve and intake manifold of an internal combustion engine and manually operated throttle control means, of a brake operatively associated with said manually operated control means for retarding the actuation thereof comprising a brake drum, a spring acting to rotate said drum, a tension member connected to said brake drum and with said manually actuated throttle control means for applying rotative movement to the drum in opposition to said spring when the throttle valve is opened, and a vacuum actuated means operatively connected to the intake at the rear of said throttle and including a vacuum actuated element operatively connected to said brake shoe.

6. The combination with the manually controlled throttle for the intake of an internal combustion engine, of a brake drum provided with a pulley, a spring acting to rotate said brake drum, a cable on said pulley connected to the operating means for said throttle, said brake drum spring acting to urge the throttle to closed position, a brake shoe coacting with said brake drum, a spring for actuating said brake shoe, and a vacuum controlled means for counteracting the thrust of said brake shoe actuating spring operatively connected to the intake at the rear of said throttle.

'7. The combination with the throttle valve and intake manifold of an internal combustion engine and manually operated throttle control means, of a brake operatively associated with said manually operated control means for retarding the actuation thereof, and a vacuum actuated means operatively connected to the intake at the rear of said throttle and including a vacuum actuated element operatively connected to said brake.

8. The combination with the throttle for the intake of an internal combustion engine and means for manually controlling said throttle, of a brake means operatively associated with said manual throttle control means, a spring for actuating said brake means to braking position, and a vacuum controlled means for counteracting said brake actuating spring operatively connected to the intake at the rear of said throttle.

9. The combination with a throttle for the intake of an internal combustion engine and manually actuated control means therefor, of a brake means operatively associated with said manual control means for retarding the actuation there- .of, and a vacuum operated means for releasing said brake operatively connected to the intake at the rear of said throttle.

10. The combination with the throttle for the intake of an internal combustion engine and means for manually controlling said throttle, of a brake means operatively associated with said manual throttle control means, and a vacuum,

controlled means for releasing said brake operatively connected to the intake at the rear of said throttle and acting to release the brake in proportion to the degree of vacuum above a predetermined value.

11. A brake device for the throttle valve of an internal combustion engine, comprising a pair of frictionally engaging relatively movable brake members, means for connecting one of said members with the actuating mechanism for said throttle valve whereby movement of said mechanism to open said valve is resisted by said brake members, and means for maintaining said members in frictional engagement to prevent undue initial opening of the valve and for relieving said members from said engagement when the vacuum in the intake manifold of the engine exceeds a predetermined value, comprising a thrust member to normally urge said members together, a flexible diaphragm connected on one side to the thrust member, a housing connected to the periphery of said diaphragm and communicating on the side thereof opposite the thrust member with the vacuum in said manifold, a thrust spring engaging the diaphragm on the last named side, said diaphragm being retracted in opposition to said spring when said vacuum exceeds said predetermined value, whereby to permit relative movement of said members and resultant full opening of the valve, and means for returning said members to initial relative position when the valve is closed.

12. A brake device for the throttle valve of an internal combustion engine, comprising a pair of frictionally engaging brake members, means for connecting one of said members with the actuating mechanism for said throttle valve, whereby movement of said mechanism to open said valve is resisted by said brake members, means for normally maintaining said members in frictional engagement to prevent undue initial opening of the valve and for relieving said members from said engagement when the vacuum in the intake manifold of the engine exceeds a predetermined value, comprising a device including a pressure responsive element, means for communicating said pressure responsive element with the vacuum in said manifold, and means for operatively connecting said element with said brake members to relieve said frictional engagement when said vacuum exceeds said predetermined value, whereby to permit movement of one of said members. and resultant full opening of the valve.

13. A control device for preventing sudden opening of the throttle valve of an internal combustion engine when the same is accelerated, comprising a brake in the form of fixed and rotatable brake members, the latter of which is operatively connected to an actuating mechanism for the throttle valve whereby opening of the valve is attended by a tendency to rotate the member, means for urging said members into frictional engagement sufficient to restrain undue rotation of said rotatable member comprising a thrust member and a spring urging said thrust member against said brake in a direction to effect said frictional engagement, and means responsive to the vacuum in the intake manifold of said engine for decreasing the thrust exerted by said thrust member for releasing said brake members from said engagement comprising a diaphragm operatively connected withthe brake member and a housing engaging the periphery of the diaphragm and in communication with said manifold, said diaphragm retracting said thrust member when the vacuum exceeds said predetermined amount.

14. A control device for preventing sudden opening of the throttle valve of an internal combustion engine when the same is accelerated, comprising a brake in the form of fixed and rotatable brake membersfthe latter of which is operatively connected to an actuating mechanism for the throttle valve whereby opening of the valve is attended by a tendency to rotate the member, means for urging said members into frictional engagement s-ufficient to restrain undue rotation of said rotatable member comprising a thrust member and a spring urging said thrust member against said brake in a direction to effect said frictional engagement, and means respon" sive to the vacuum in the intake manifold of said engine for decreasing the thrust exerted by said thrust member for releasing said brake members from said engagement.

15. A control device for preventing sudden opening of the throttle of an internal combustion engine when the same is accelerated, comprising a brake in the form of fixed and movable brake members, the latter of which is operatively connected to an actuating mechanism for the throttle valve whereby opening of the valve is attended by a tendency to move the member, means for urging said members into frictional engagement sufficient to restrain undue movement of said movable member, and means responsive to the vacuum in the intake manifold of said engine for releasing said brake members from said engagement.

15. A control device to prevent sudden opening of the throttle valve of an internal combustion engine, comprising a pair of brake members, means for connecting one of said members with the actuating mechanism for the throttle valve, means for urging the other brake member transversely of the direction of movement of said one of said members in response to said actuating mechanism, whereby to frictionally engage said one of said members to restrain undue movement thereof, comprising a thrust member engaging said other brake member and spring means normally urging said thrust member against said other brake member, and means for decreasing thrust on said other brake member to permit increased movement of the said one of said members when the vacuum in the intake manifold of the engine exceeds a predetermined amount comprising a diaphragm connected to the thrust member and means for communicating the diaphragm with the vacuum in said manifold.

17. A control device to prevent sudden opening of the throttle valve of an internal combustion engine comprising a pair of brake members, means for connecting one of said members with the actuating mechanism for the throttle valve, means for urging the other brake member transversely of the direction of movement of said one of said members in response to said actuating mechanism, whereby to frictionally engage said one of said members sufficiently to restrain undue movement thereof, and means responsive to the vacuum in the intake manifold of the engine for decreasing the force exerted on said other member to permit increased movement of the said one of said members.

HENRY H. MERRIMAN. 

